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Amy Robach is preparing to fight. The ABC News' journalist made her return to "Good Morning America" on Dec. 5, after undergoing a double mastectomy following her breast cancer diagnosis. Robach, 40, has completed the first step in her fight against cancer, but still has a long journey ahead.

"I am feeling really good," she shared on GMA. "It's three weeks to the day that I went into surgery. Physically, I feel remarkably well. Mentally, it's another challenge because that was phase one."

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The veteran journalist was diagnosed with breast cancer after getting her first-ever mammogram live on "GMA" in October. While undergoing a double mastectomy, doctors discovered the cancer had spread to her sentinel lymph node, or the first few lymph nodes into which a tumor drains.

"That was the devastating news to me," Robach explained on Monday. "When I woke up, the first question I asked was, 'Did it spread to my lymph nodes?,' because that's the difference between chemo and no chemo."

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Robach, who is married to actor Andrew Shue and mom to two daughters and three stepsons, will now undergo four months of chemotherapy beginning on Dec. 16. She said she's looking to co-anchor Robin Roberts, a breast cancer and myelodysplastic syndrome survivor, to help her get through it.

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"You give me strength, Robin, because it is important to get up and have something to do each day, even if you don't feel great," Robach said. "Some people have it harder than I do so I will take it hour by hour."


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